104 THE VAGARIES OF COLOUR, ETC. 



creased length of the antennae is another male 

 characteristic. This is carried to an extraordinary 

 development in what is called the " long horned 

 bee" ; this bee, which is pretty common in some 

 places, has antennae which, when directed back- 

 wards, are almost as long as its body the female 

 has quite an ordinary pair. 



Another set of male characters which are of 

 great value to systematists lies in the hidden 

 apical segments of the underside ; although 

 these are hidden, being telescoped up inside the 

 segments which close the apical opening of the 

 body, they often assume most curious and 

 beautiful forms, and are characters whereby 

 the males of a species may be determined with 

 certainty when the females defy all one's endeav- 

 ours to discover their identity. 



